This application, and the innovations and related subject matter disclosed herein, (collectively referred to as the “disclosure”) generally concern systems for providing sound fields having smoothly changing, or constant, directivity with frequency. More particularly but not exclusively, some disclosed principles are embodied as an audio device configured to render an approximation to a desired sound field throughout a listening environment by rendering a truncated decomposition of the desired sound field. In some, but not all, embodiments, the desired sound field can be user defined.
Conventional audio systems and acoustic beam formers project a sound field into a listening environment in a fixed, or stationary, manner regardless of the listening environment in which they are installed. As well, directivity of conventional audio systems varies with, among other parameters, acoustic frequency.
Consequently, many conventional systems offer “optimal” playback in only one installation arrangement and at one listening position within a given listening environment. As well, many conventional audio systems are best-suited for only certain types or classes of audio (e.g., certain classes of music, motion-picture soundtracks, etc.). Nonetheless, a given audio system will generally be installed throughout a wide variety of environments, e.g., room sizes, elevations within a room, desk- or table-tops, book cases, near walls, near room corners, etc. And, many audio systems for consumers will be called on to playback a variety of classes of music, as well as motion-picture soundtracks.
In short, conventional audio systems provide deficient listening experiences for users.
Thus, a need exists for an audio system capable of rendering a sound field tailored to the listening environment in which it is installed. A need also exists for an audio system capable of rendering customizable, or user-definable, sound fields. Further, a need exists for an audio system that provides smooth directivity and/or smoothly varying sound fields throughout the audible spectrum of frequencies, or sub-bands thereof.